The present invention relates to a coupler device for hose connections and to a method for connecting such endform to a hose. More particularly, the present invention relates to a coupling endform device including a barb having an asymmetric barb profile which provides improved coupling retention and sealing properties while requiring no additional coupling effort during assembly of the coupling device to a hose, compared to a conventional coupling device having a symmetrical circular barb profile.
Hose coupling endform devices are known. For example, commonly assigned U.S. Pat. No. 6,880,862 to Mobley teaches a coupling device for connecting a polymeric tubing having a first conductive inner surface to the open end of a hose having a second conductive surface such that conductive continuity is maintained between the polymeric tube and the hose. U.S. Pat. No. 3,653,692 to Henson describes an elastomeric hose connected to a nipple having a circumferential barb. The hose is stretched allowing a ring member to slide down the hose and over the barbed nipple where it creates a compression on the hose when the hose is no longer stretched. U.S. Pat. Nos. 6,733,047 to Stieler; 6,637,779 to Andre; 6,634,679 to Stieler; 6,568,714 to Stripe; 6,412,826 to Kulevsky, et al; 6,378,908 to Walker, et al.; 6,113,151 to Beans; 5,711,549 to Beans; 5,707,087 to Ridenour et al; 5,516,157 to Williamson; 5,516,156 Williamson; 5,423,581 to Saylers; 4,114,930 to Perkins et al; and 3,689,111 to Osmun, all teach coupling devices for connecting tubing to a fitting assembly to prevent leaks in a fluid transport system.
It is essential that fluid transfer hoses such as those employed in fluid transfer assemblies on power steering pressure and return lines exhibit tight tolerances and high strength to prevent the fluid from leaking from the assembly. Current practice in the hose connector art requires that a heavy clamping or crimping force be applied about a collar around the hose and the fitting to provide a fluid-tight seal and to provide pull-off resistance to the assembly. In such cases, the hose is compressed radially inward to make a seal. However, it is difficult to make a leak-tight seal, because the tube, even though malleable, tends to have enough elasticity to relax and deform upon release of the clamping or crimping pressure sufficient to compromise the fluid-tight seal, particularly when the fluid is under high pressure for an extended period of time. Therefore, while conventional connectors generally are able to achieve the required tolerances or the strength required to provide good sealing and hose retention properties, these properties are generally accompanied by undesirable high assembly effort. For example, a fluid transfer assembly designed to achieve low push-on force throughout its dimensional tolerance, will have a high probability of poor to mediocre coupling tensile, burst and impulse performance.
Accordingly, it would be advantageous to provide a hose endform connector that would increase coupling retention using both clamped and crimped assembly design while requiring reduced assembly effort force.